Bold warrior upgrade to O-360-A4M

clint24@me.com

Hi folks. Need some advice. Scott, please weigh in..... my 160 engine had a cylinder that lost compression and we borescoped the cam shaft when we pulled the jug. Cam shaft was pitted and a small blemish was noted. at 1800 hours, I decided to buy out the partners (who had no stomach for an overhaul) go to the bank and make this my forever plane. I am STC upgrading through Bold Warrior to a 180, Lycoming O-360-A4M by PennYan Aero. After two months, it appears it will ship soon. They test it for 1.5 hours in their booth. I have read the break-in procedures, oil changes, etc on the new engine. I would appreciate ANY comments, advice or experience anyone has had with a rebuilt Lycoming. What you did, what you wish you would have done during break in. This "infant paralysis" thing I hear about on new engines has me concerned. Thanks to all my Piper buds. Marc.

griff390

Marc;

I've done a break-in on 3 engines. Two were in my plane, and I helped on 1 for a friend. I've always followed the break-in procedures to the letter, and have not had any problems (knock on wood).

My most recent was a factory zero time engine from Lycoming. There was a fair amount of time spent on the ground running the engine at specific RPM's and time, then shut down, check for leaks, etc. In some cases, the engine had to cool before the next step, while others the engine was restarted while still warm, and moved on. My wife set up a tri-pod and videoed the whole procedure for posterity, but later I realized how brilliant that was because if something happened, there was video proof that I had followed the procedure exactly.

Once the ground break-in portion was complete, a flying break-in followed with specific parameters to follow. I had to fly for something like 40 minutes at or near full throttle. I called the tower and told them that I was breaking in a new engine and wanted to stay a thousand feet or so directly above the airport in case of a failure. They understood and cleared me, so I flew a racetrack pattern over the airport for the specified time. It was fun!

Once I had completed the initial break-in, I flew a 400+ mile x-country flight, still following the recommendations. I seem to recall varying the RPM for specified time e.g. 2,400 RPM for 30 min, then 2,500 RPM for 30 min., etc. Varying the RPM helps the rings and other parts seat correctly. The rebuilder/manufacturer will tell you when you can begin running the engine unrestricted.

Bottom line is follow the rebuilder's advice to the letter. If the builder recommends running full rich, or an oil change at 5 hours, do it. During the initial flying break-in, I'd recommend flying a racetrack pattern above your airport, and stay within gliding distance. I would not bring a passenger(s) during this portion. There's no rule against it, but if you have a problem, it's better to have only 1 person in danger than 2 or 3. That's just math.

When I fly now, I treat the engine kindly. I don't push it hard, and it gives me great performance.

Scott Sherer

Good answer Griff. Nothing to add here except that Bold Warriors is an excellent company. I did an article on them last year in Pipers magazine. With all of the Knots2U speed mods and the new engine, it will be faster than an Arrow. Let us know how it turns out.

clint24@me.com

Thank you Griff and Scott. Much appreciated advice.

Johnjetman

I have Warrior -151 that I was considering a Bold Warrior conversion for. My concern was the slightly higher weight and additional forward c.g. Any thoughts on that? Thanks.

griff390

Johnjetman;

The Bold Warrior STC covers the weight difference, and provides new POH performance numbers. See their website at https://www.bold-warrior.com/the-country-annex. According to their website, you'll only lose 12 lbs useful load, but you'll need a new weight/balance regardless.

Johnjetman

Thanks Griff, I’ve looked over the website. I think I can live with 12 lbs. Just not sure about the forward cg. Time for a bit more research. I like the idea of being able to take the plane to them to get it all done. It should cost about what the plane is worth...Ah aviation.

MikeJJ

With regard to break-in, Griff is right on the money. Follow the published break-in procedures to the letter. I also had to break-in a factory zero time engine in my Cherokee 180. If I had to do it again, I would opt for cooler weather in the fall. In that way you can get the required percent power at higher altitudes! I recall having to stay uncomfortably low for long periods of time. Something I enjoy in a helicopter but not in the Cherokee!

arrow76r

I had the opposite situation breaking in my Lyc overhauled IO-360. I had to fly about 80 miles to get DOWN to an altitude where I could see 75% power even in the winter!! Normally WOT in my home base (7000 MSL) vicinity is just over about 66% . Fortunately Lycoming had done the major running-in before they shipped it to my mech. After just over 100 hours now the oil filter is clean and the oil consumption is about 1 qt/20 hours.

Scott Sherer

This just in from Bold Warrior:

_It’s all done but the signature, literally.

Yesterday The DAR (Designated Airworthiness Representative) came to visit the Bold Warrior project along with his EAG manager. They completed the inspection and hand delivered it to the ACO for processing. Which means probably a week or so of running back thru the office and it should be done. At this point it is just a formality, there are no more approvals needed. So I have updated the Bold-Warrior.com website and have an owner flying in from California to have the conversion done here in Atlanta asap.

Talk to you soon, Kent
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